U.S. Pat. Nos. 4,193,654, 4,210,376 and 4,221,458 show a known type of electrical connector assembly comprising a plug and a receptacle which is coming into widespread use in the communications industry and on computer and computer related equipment. The receptacles shown in the above identified U.S. Patents are dimensioned to receive connector plugs of the general type shown in U.S. Pat. No. 3,860,316.
When connector assemblies of the type identified above are used in telephone equipment, it has ordinarily not been necessary in the past to provide either shielding for the connector parts or keying of individual plugs to individual receptacles. The requirement for shielding, however, is becoming widespread and many future plugs and receptacles will require such shielding.
It is also desirable to provide a keying system for connector plugs and receptacles as described in the above identified U.S. Patents, particularly where the connectors are used in computer-type equipment. Connector assemblies of the type described above will, in the future, be manufactured with greater numbers of terminals than are required in ordinary telephone equipment and several connector assemblies might be used in close proximity to each other so that mis-mating of connector plugs and receptacles can result with the potential for serious damage to the equipment.
The provision of a keying system in combination with a shielding system on connector assemblies of the type under consideration presents problems which are not ordinarily encountered when it is desired to provide either shielding or a keying system on the parts of a connector assembly. An effective shielding system requires that when the plug of the assembly is inserted into the receptacle, the shielding material on the plug must be placed in contact with the shielding material on the receptacle and the provision of suitable contact means which satisfies this requirement interferes with the function of most types of keying systems for connector assemblies. The present invention is thus directed to that achievement of a connector assembly having both an effective shielding system and a keying system which does not interfere with the effectiveness of the shielding system.
A preferred embodiment of the invention comprises an electrical connector receptacle of the type comprising a molded insulating housing having a mating end, a rearward end, oppositely facing first and second housing sidewalls and oppositely facing housing endwalls extending from the mating end to the rearward end. A plug-receiving opening extends into the mating end, the opening having opposed first and second opening sidewalls which are proximate to the first and second housing sidewalls, and opposed opening endwalls. A plurality of receptacle terminals are contained in the receptacle, the terminals being arranged in a row which extends between the opening endwalls. Each terminal has a cantilever spring contact portion which extends from the second opening sidewall at a location proximate to the mating end diagonally into the opening towards the inner end of the opening. The opening is dimensioned to receive a plug having plug terminals therein which contact the cantilever spring contact portions. The receptacle is characterized in that it has at least one key on the first opening sidewall, the key having a leading end and an inner end, the leading end being proximate to, and spaced from, the mating end of the housing and the inner end being remote from the mating end of the housing. A receptacle shield is provided on the housing, the receptacle shield extending over the mating end and to the plug-receiving opening and having shield contact extensions extending into the plug-receiving opening for contacting the plug shield on a complementary plug upon insertion of the plug into the opening. The shield contact extensions are adjacent to the first opening sidewall.
In accordance with a further embodiment, the receptacle shield is of stamped and formed sheet metal and the shield contact extensions are cantilever springs which are integral with the shield and which extend diagonally into the plug-receiving opening.
In accordance with a further embodiment, a connector assembly comprises a plug and a receptacle, the receptacle being as described above and the plug having a plug shield. The plug shield overlaps the forward portions of the plug which are received in the plug-receiving opening of the receptacle and the plug shield extends to the rearward end of the plug. The keyway which receives the key in the receptacle is provided in the plug housing in the forward portions thereof.